src/modules/extra/m_mysql.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2004 ChatSpike-Dev.
   6  *                     E-mail:
   7  *              <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *          the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 #include <stdio.h>
  20 #include <string>
  21 #include <mysql.h>
  22 #include <pthread.h>
  23 #include "users.h"
  24 #include "channels.h"
  25 #include "modules.h"
  26 #include "helperfuncs.h"
  27 #include "m_sqlv2.h"
  28
  29 /* VERSION 2 API: With nonblocking (threaded) requests */
  30
  31 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
  32 /* $CompileFlags: `mysql_config --include` */
  33 /* $LinkerFlags: `mysql_config --libs_r` `perl ../mysql_rpath.pl` */
  34
  35 /* THE NONBLOCKING MYSQL API!
  36  *
  37  * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
  38  * that instead, you should thread your program. This is what i've done here to allow for
  39  * asyncronous SQL requests via mysql. The way this works is as follows:
  40  *
  41  * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
  42  * using a queue with priorities. There is a mutex on either end which prevents two threads
  43  * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
  44  * worker thread wakes up, and checks if there is a request at the head of its queue.
  45  * If there is, it processes this request, blocking the worker thread but leaving the ircd
  46  * thread to go about its business as usual. During this period, the ircd thread is able
  47  * to insert futher pending requests into the queue.
  48  *
  49  * Once the processing of a request is complete, it is removed from the incoming queue to
  50  * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
  51  * ircd thread (via a loopback socket) of the fact a result is available, by sending the
  52  * connection ID through the connection.
  53  *
  54  * The ircd thread then mutexes the queue once more, reads the outbound response off the head
  55  * of the queue, and sends it on its way to the original calling module.
  56  *
  57  * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
  58  * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
  59  * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
  60  * however, if we were to call a module's OnRequest even from within a thread which was not the
  61  * one the module was originally instantiated upon, there is a chance of all hell breaking loose
  62  * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
  63  * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
  64  * gauranteed threadsafe!)
  65  *
  66  * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
  67  */
  68
  69
  70 class SQLConnection;
  71 class Notifier;
  72
  73 extern InspIRCd* ServerInstance;
  74 typedef std::map<std::string, SQLConnection*> ConnMap;
  75 bool giveup = false;
  76 static Module* SQLModule = NULL;
  77 static Notifier* MessagePipe = NULL;
  78 int QueueFD = -1;
  79
  80
  81 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
  82 #define mysql_field_count mysql_num_fields
  83 #endif
  84
  85 typedef std::deque<SQLresult*> ResultQueue;
  86
  87 class QueryQueue : public classbase
  88 {
  89 private:
  90         typedef std::deque<SQLrequest> ReqDeque;
  91
  92         ReqDeque priority;      /* The priority queue */
  93         ReqDeque normal;        /* The 'normal' queue */
  94         enum { PRI, NOR, NON } which;   /* Which queue the currently active element is at the front of */
  95
  96 public:
  97         QueryQueue()
  98         : which(NON)
  99         {
 100         }
 101
 102         void push(const SQLrequest &q)
 103         {
 104                 log(DEBUG, "QueryQueue::push(): Adding %s query to queue: %s", ((q.pri) ? "priority" : "non-priority"), q.query.q.c_str());
 105
 106                 if(q.pri)
 107                         priority.push_back(q);
 108                 else
 109                         normal.push_back(q);
 110         }
 111
 112         void pop()
 113         {
 114                 if((which == PRI) && priority.size())
 115                 {
 116                         priority.pop_front();
 117                 }
 118                 else if((which == NOR) && normal.size())
 119                 {
 120                         normal.pop_front();
 121                 }
 122
 123                 /* Reset this */
 124                 which = NON;
 125
 126                 /* Silently do nothing if there was no element to pop() */
 127         }
 128
 129         SQLrequest& front()
 130         {
 131                 switch(which)
 132                 {
 133                         case PRI:
 134                                 return priority.front();
 135                         case NOR:
 136                                 return normal.front();
 137                         default:
 138                                 if(priority.size())
 139                                 {
 140                                         which = PRI;
 141                                         return priority.front();
 142                                 }
 143
 144                                 if(normal.size())
 145                                 {
 146                                         which = NOR;
 147                                         return normal.front();
 148                                 }
 149
 150                                 /* This will probably result in a segfault,
 151                                  * but the caller should have checked totalsize()
 152                                  * first so..meh - moron :p
 153                                  */
 154
 155                                 return priority.front();
 156                 }
 157         }
 158
 159         std::pair<int, int> size()
 160         {
 161                 return std::make_pair(priority.size(), normal.size());
 162         }
 163
 164         int totalsize()
 165         {
 166                 return priority.size() + normal.size();
 167         }
 168
 169         void PurgeModule(Module* mod)
 170         {
 171                 DoPurgeModule(mod, priority);
 172                 DoPurgeModule(mod, normal);
 173         }
 174
 175 private:
 176         void DoPurgeModule(Module* mod, ReqDeque& q)
 177         {
 178                 for(ReqDeque::iterator iter = q.begin(); iter != q.end(); iter++)
 179                 {
 180                         if(iter->GetSource() == mod)
 181                         {
 182                                 if(iter->id == front().id)
 183                                 {
 184                                         /* It's the currently active query.. :x */
 185                                         iter->SetSource(NULL);
 186                                 }
 187                                 else
 188                                 {
 189                                         /* It hasn't been executed yet..just remove it */
 190                                         iter = q.erase(iter);
 191                                 }
 192                         }
 193                 }
 194         }
 195 };
 196
 197 /* A mutex to wrap around queue accesses */
 198 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
 199
 200 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
 201
 202 class MySQLresult : public SQLresult
 203 {
 204         int currentrow;
 205         //std::vector<std::map<std::string,std::string> > results;
 206         std::vector<std::string> colnames;
 207         std::vector<SQLfieldList> fieldlists;
 208         SQLfieldMap* fieldmap;
 209         int rows;
 210         int cols;
 211  public:
 212
 213         MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
 214         {
 215                 /* A number of affected rows from from mysql_affected_rows.
 216                  */
 217                 log(DEBUG,"Created new MySQLresult of non-error type");
 218                 fieldlists.clear();
 219                 rows = 0;
 220                 if (affected_rows >= 1)
 221                 {
 222                         rows = affected_rows;
 223                         fieldlists.resize(rows);
 224                 }
 225                 unsigned int field_count = 0;
 226                 if (res)
 227                 {
 228                         MYSQL_ROW row;
 229                         int n = 0;
 230                         while ((row = mysql_fetch_row(res)))
 231                         {
 232                                 if (fieldlists.size() < (unsigned int)rows+1)
 233                                 {
 234                                         fieldlists.resize(fieldlists.size()+1);
 235                                 }
 236                                 field_count = 0;
 237                                 MYSQL_FIELD *fields = mysql_fetch_fields(res);
 238                                 if(mysql_num_fields(res) == 0)
 239                                         break;
 240                                 if (fields && mysql_num_fields(res))
 241                                 {
 242                                         colnames.clear();
 243                                         while (field_count < mysql_num_fields(res))
 244                                         {
 245                                                 std::string a = (fields[field_count].name ? fields[field_count].name : "");
 246                                                 std::string b = (row[field_count] ? row[field_count] : "");
 247                                                 SQLfield sqlf(b, !row[field_count]);
 248                                                 colnames.push_back(a);
 249                                                 fieldlists[n].push_back(sqlf);
 250                                                 log(DEBUG,"Inc field count to %d",field_count+1);
 251                                                 field_count++;
 252                                         }
 253                                         n++;
 254                                 }
 255                                 rows++;
 256                         }
 257                         cols = field_count;
 258                         mysql_free_result(res);
 259                 }
 260                 log(DEBUG, "Created new MySQL result; %d rows, %d columns", rows, cols);
 261         }
 262
 263         MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
 264         {
 265                 rows = 0;
 266                 cols = 0;
 267                 error = e;
 268                 log(DEBUG,"Created new MySQLresult of error type");
 269         }
 270
 271         ~MySQLresult()
 272         {
 273         }
 274
 275         virtual int Rows()
 276         {
 277                 return rows;
 278         }
 279
 280         virtual int Cols()
 281         {
 282                 return cols;
 283         }
 284
 285         virtual std::string ColName(int column)
 286         {
 287                 if (column < (int)colnames.size())
 288                 {
 289                         return colnames[column];
 290                 }
 291                 else
 292                 {
 293                         throw SQLbadColName();
 294                 }
 295                 return "";
 296         }
 297
 298         virtual int ColNum(const std::string &column)
 299         {
 300                 for (unsigned int i = 0; i < colnames.size(); i++)
 301                 {
 302                         if (column == colnames[i])
 303                                 return i;
 304                 }
 305                 throw SQLbadColName();
 306                 return 0;
 307         }
 308
 309         virtual SQLfield GetValue(int row, int column)
 310         {
 311                 if ((row >= 0) && (row < rows) && (column >= 0) && (column < cols))
 312                 {
 313                         return fieldlists[row][column];
 314                 }
 315
 316                 log(DEBUG,"Danger will robinson, we don't have row %d, column %d!", row, column);
 317                 throw SQLbadColName();
 318
 319                 /* XXX: We never actually get here because of the throw */
 320                 return SQLfield("",true);
 321         }
 322
 323         virtual SQLfieldList& GetRow()
 324         {
 325                 return fieldlists[currentrow];
 326         }
 327
 328         virtual SQLfieldMap& GetRowMap()
 329         {
 330                 fieldmap = new SQLfieldMap();
 331
 332                 for (int i = 0; i < cols; i++)
 333                 {
 334                         fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
 335                 }
 336                 currentrow++;
 337
 338                 return *fieldmap;
 339         }
 340
 341         virtual SQLfieldList* GetRowPtr()
 342         {
 343                 return &fieldlists[currentrow++];
 344         }
 345
 346         virtual SQLfieldMap* GetRowMapPtr()
 347         {
 348                 fieldmap = new SQLfieldMap();
 349
 350                 for (int i = 0; i < cols; i++)
 351                 {
 352                         fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
 353                 }
 354                 currentrow++;
 355
 356                 return fieldmap;
 357         }
 358
 359         virtual void Free(SQLfieldMap* fm)
 360         {
 361                 delete fm;
 362         }
 363
 364         virtual void Free(SQLfieldList* fl)
 365         {
 366                 /* XXX: Yes, this is SUPPOSED to do nothing, we
 367                  * dont want to free our fieldlist until we
 368                  * destruct the object. Unlike the pgsql module,
 369                  * we only have the one.
 370                  */
 371         }
 372 };
 373
 374 class SQLConnection;
 375
 376 void NotifyMainThread(SQLConnection* connection_with_new_result);
 377
 378 class SQLConnection : public classbase
 379 {
 380  protected:
 381
 382         MYSQL connection;
 383         MYSQL_RES *res;
 384         MYSQL_ROW row;
 385         std::string host;
 386         std::string user;
 387         std::string pass;
 388         std::string db;
 389         std::map<std::string,std::string> thisrow;
 390         bool Enabled;
 391         std::string id;
 392
 393  public:
 394
 395         QueryQueue queue;
 396         ResultQueue rq;
 397
 398         // This constructor creates an SQLConnection object with the given credentials, and creates the underlying
 399         // MYSQL struct, but does not connect yet.
 400         SQLConnection(std::string thishost, std::string thisuser, std::string thispass, std::string thisdb, const std::string &myid)
 401         {
 402                 this->Enabled = true;
 403                 this->host = thishost;
 404                 this->user = thisuser;
 405                 this->pass = thispass;
 406                 this->db = thisdb;
 407                 this->id = myid;
 408         }
 409
 410         // This method connects to the database using the credentials supplied to the constructor, and returns
 411         // true upon success.
 412         bool Connect()
 413         {
 414                 unsigned int timeout = 1;
 415                 mysql_init(&connection);
 416                 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
 417                 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
 418         }
 419
 420         void DoLeadingQuery()
 421         {
 422                 if (!CheckConnection())
 423                         return;
 424
 425                 /* Parse the command string and dispatch it to mysql */
 426                 SQLrequest& req = queue.front();
 427                 log(DEBUG,"DO QUERY: %s",req.query.q.c_str());
 428
 429                 /* Pointer to the buffer we screw around with substitution in */
 430                 char* query;
 431
 432                 /* Pointer to the current end of query, where we append new stuff */
 433                 char* queryend;
 434
 435                 /* Total length of the unescaped parameters */
 436                 unsigned long paramlen;
 437
 438                 /* Total length of query, used for binary-safety in mysql_real_query */
 439                 unsigned long querylength = 0;
 440
 441                 paramlen = 0;
 442
 443                 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
 444                 {
 445                         paramlen += i->size();
 446                 }
 447
 448                 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
 449                  * sizeofquery + (totalparamlength*2) + 1
 450                  *
 451                  * The +1 is for null-terminating the string for mysql_real_escape_string
 452                  */
 453
 454                 query = new char[req.query.q.length() + (paramlen*2)];
 455                 queryend = query;
 456
 457                 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
 458                  * the parameters into it...
 459                  */
 460
 461                 for(unsigned long i = 0; i < req.query.q.length(); i++)
 462                 {
 463                         if(req.query.q[i] == '?')
 464                         {
 465                                 /* We found a place to substitute..what fun.
 466                                  * use mysql calls to escape and write the
 467                                  * escaped string onto the end of our query buffer,
 468                                  * then we "just" need to make sure queryend is
 469                                  * pointing at the right place.
 470                                  */
 471                                 if(req.query.p.size())
 472                                 {
 473                                         unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
 474
 475                                         queryend += len;
 476                                         req.query.p.pop_front();
 477                                 }
 478                                 else
 479                                 {
 480                                         log(DEBUG, "Found a substitution location but no parameter to substitute :|");
 481                                         break;
 482                                 }
 483                         }
 484                         else
 485                         {
 486                                 *queryend = req.query.q[i];
 487                                 queryend++;
 488                         }
 489                         querylength++;
 490                 }
 491
 492                 *queryend = 0;
 493
 494                 log(DEBUG, "Attempting to dispatch query: %s", query);
 495
 496                 pthread_mutex_lock(&queue_mutex);
 497                 req.query.q = query;
 498                 pthread_mutex_unlock(&queue_mutex);
 499
 500                 log(DEBUG,"REQUEST ID: %d",req.id);
 501
 502                 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
 503                 {
 504                         /* Successfull query */
 505                         res = mysql_use_result(&connection);
 506                         unsigned long rows = mysql_affected_rows(&connection);
 507                         MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
 508                         r->dbid = this->GetID();
 509                         r->query = req.query.q;
 510                         /* Put this new result onto the results queue.
 511                          * XXX: Remember to mutex the queue!
 512                          */
 513                         pthread_mutex_lock(&results_mutex);
 514                         rq.push_back(r);
 515                         pthread_mutex_unlock(&results_mutex);
 516                 }
 517                 else
 518                 {
 519                         /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
 520                          * possible error numbers and error messages */
 521                         log(DEBUG,"SQL ERROR: %s",mysql_error(&connection));
 522                         SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
 523                         MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
 524                         r->dbid = this->GetID();
 525                         r->query = req.query.q;
 526
 527                         pthread_mutex_lock(&results_mutex);
 528                         rq.push_back(r);
 529                         pthread_mutex_unlock(&results_mutex);
 530                 }
 531
 532                 /* Now signal the main thread that we've got a result to process.
 533                  * Pass them this connection id as what to examine
 534                  */
 535
 536                 NotifyMainThread(this);
 537         }
 538
 539         bool ConnectionLost()
 540         {
 541                 if (&connection) {
 542                         return (mysql_ping(&connection) != 0);
 543                 }
 544                 else return false;
 545         }
 546
 547         bool CheckConnection()
 548         {
 549                 if (ConnectionLost()) {
 550                         return Connect();
 551                 }
 552                 else return true;
 553         }
 554
 555         std::string GetError()
 556         {
 557                 return mysql_error(&connection);
 558         }
 559
 560         const std::string& GetID()
 561         {
 562                 return id;
 563         }
 564
 565         std::string GetHost()
 566         {
 567                 return host;
 568         }
 569
 570         void SetEnable(bool Enable)
 571         {
 572                 Enabled = Enable;
 573         }
 574
 575         bool IsEnabled()
 576         {
 577                 return Enabled;
 578         }
 579
 580 };
 581
 582 ConnMap Connections;
 583
 584 void ConnectDatabases(Server* Srv)
 585 {
 586         for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
 587         {
 588                 i->second->SetEnable(true);
 589                 if (i->second->Connect())
 590                 {
 591                         Srv->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
 592                 }
 593                 else
 594                 {
 595                         Srv->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
 596                         i->second->SetEnable(false);
 597                 }
 598         }
 599 }
 600
 601
 602 void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
 603 {
 604         Srv->Log(DEFAULT,"SQL: Loading database settings");
 605         Connections.clear();
 606         Srv->Log(DEBUG,"Cleared connections");
 607         for (int j =0; j < ThisConf->Enumerate("database"); j++)
 608         {
 609                 std::string db = ThisConf->ReadValue("database","name",j);
 610                 std::string user = ThisConf->ReadValue("database","username",j);
 611                 std::string pass = ThisConf->ReadValue("database","password",j);
 612                 std::string host = ThisConf->ReadValue("database","hostname",j);
 613                 std::string id = ThisConf->ReadValue("database","id",j);
 614                 Srv->Log(DEBUG,"Read database settings");
 615                 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
 616                 {
 617                         SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
 618                         Srv->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
 619                         Connections[id] = ThisSQL;
 620                         Srv->Log(DEBUG,"Pushed back connection");
 621                 }
 622         }
 623         ConnectDatabases(Srv);
 624 }
 625
 626 void NotifyMainThread(SQLConnection* connection_with_new_result)
 627 {
 628         /* Here we write() to the socket the main thread has open
 629          * and we connect()ed back to before our thread became active.
 630          * The main thread is using a nonblocking socket tied into
 631          * the socket engine, so they wont block and they'll receive
 632          * nearly instant notification. Because we're in a seperate
 633          * thread, we can just use standard connect(), and we can
 634          * block if we like. We just send the connection id of the
 635          * connection back.
 636          */
 637         log(DEBUG,"Notify of result on connection: %s",connection_with_new_result->GetID().c_str());
 638         if (send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0) < 1) // add one for null terminator
 639         {
 640                 log(DEBUG,"Error writing to QueueFD: %s",strerror(errno));
 641         }
 642         log(DEBUG,"Sent it on its way via fd=%d",QueueFD);
 643 }
 644
 645 void* DispatcherThread(void* arg);
 646
 647 class Notifier : public InspSocket
 648 {
 649         sockaddr_in sock_us;
 650         socklen_t uslen;
 651         Server* Srv;
 652
 653  public:
 654
 655         /* Create a socket on a random port. Let the tcp stack allocate us an available port */
 656         Notifier(Server* S) : InspSocket("127.0.0.1", 0, true, 3000), Srv(S)
 657         {
 658                 uslen = sizeof(sock_us);
 659                 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
 660                 {
 661                         throw ModuleException("Could not create random listening port on localhost");
 662                 }
 663         }
 664
 665         Notifier(int newfd, char* ip, Server* S) : InspSocket(newfd, ip), Srv(S)
 666         {
 667                 log(DEBUG,"Constructor of new socket");
 668         }
 669
 670         /* Using getsockname and ntohs, we can determine which port number we were allocated */
 671         int GetPort()
 672         {
 673                 return ntohs(sock_us.sin_port);
 674         }
 675
 676         virtual int OnIncomingConnection(int newsock, char* ip)
 677         {
 678                 log(DEBUG,"Inbound connection on fd %d!",newsock);
 679                 Notifier* n = new Notifier(newsock, ip, Srv);
 680                 Srv->AddSocket(n);
 681                 return true;
 682         }
 683
 684         virtual bool OnDataReady()
 685         {
 686                 log(DEBUG,"Inbound data!");
 687                 char* data = this->Read();
 688                 ConnMap::iterator iter;
 689
 690                 if (data && *data)
 691                 {
 692                         log(DEBUG,"Looking for connection %s",data);
 693                         /* We expect to be sent a null terminated string */
 694                         if((iter = Connections.find(data)) != Connections.end())
 695                         {
 696                                 log(DEBUG,"Found it!");
 697
 698                                 /* Lock the mutex, send back the data */
 699                                 pthread_mutex_lock(&results_mutex);
 700                                 ResultQueue::iterator n = iter->second->rq.begin();
 701                                 (*n)->Send();
 702                                 iter->second->rq.pop_front();
 703                                 pthread_mutex_unlock(&results_mutex);
 704                                 return true;
 705                         }
 706                 }
 707
 708                 return false;
 709         }
 710 };
 711
 712 class ModuleSQL : public Module
 713 {
 714  public:
 715         Server *Srv;
 716         ConfigReader *Conf;
 717         pthread_t Dispatcher;
 718         int currid;
 719
 720         void Implements(char* List)
 721         {
 722                 List[I_OnRehash] = List[I_OnRequest] = 1;
 723         }
 724
 725         unsigned long NewID()
 726         {
 727                 if (currid+1 == 0)
 728                         currid++;
 729                 return ++currid;
 730         }
 731
 732         char* OnRequest(Request* request)
 733         {
 734                 if(strcmp(SQLREQID, request->GetData()) == 0)
 735                 {
 736                         SQLrequest* req = (SQLrequest*)request;
 737
 738                         /* XXX: Lock */
 739                         pthread_mutex_lock(&queue_mutex);
 740
 741                         ConnMap::iterator iter;
 742
 743                         char* returnval = NULL;
 744
 745                         log(DEBUG, "Got query: '%s' with %d replacement parameters on id '%s'", req->query.q.c_str(), req->query.p.size(), req->dbid.c_str());
 746
 747                         if((iter = Connections.find(req->dbid)) != Connections.end())
 748                         {
 749                                 req->id = NewID();
 750                                 iter->second->queue.push(*req);
 751                                 returnval = SQLSUCCESS;
 752                         }
 753                         else
 754                         {
 755                                 req->error.Id(BAD_DBID);
 756                         }
 757
 758                         pthread_mutex_unlock(&queue_mutex);
 759                         /* XXX: Unlock */
 760
 761                         return returnval;
 762                 }
 763
 764                 log(DEBUG, "Got unsupported API version string: %s", request->GetData());
 765
 766                 return NULL;
 767         }
 768
 769         ModuleSQL(Server* Me)
 770                 : Module::Module(Me)
 771         {
 772                 Srv = Me;
 773                 Conf = new ConfigReader();
 774                 currid = 0;
 775                 SQLModule = this;
 776
 777                 MessagePipe = new Notifier(Srv);
 778                 Srv->AddSocket(MessagePipe);
 779                 log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
 780
 781                 pthread_attr_t attribs;
 782                 pthread_attr_init(&attribs);
 783                 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
 784                 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
 785                 {
 786                         throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
 787                 }
 788                 if (!Srv->PublishFeature("SQL", this))
 789                 {
 790                         /* Tell worker thread to exit NOW */
 791                         giveup = true;
 792                         throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
 793                 }
 794         }
 795
 796         virtual ~ModuleSQL()
 797         {
 798                 DELETE(Conf);
 799         }
 800
 801         virtual void OnRehash(const std::string &parameter)
 802         {
 803                 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
 804         }
 805
 806         virtual Version GetVersion()
 807         {
 808                 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
 809         }
 810
 811 };
 812
 813 void* DispatcherThread(void* arg)
 814 {
 815         log(DEBUG,"Starting Dispatcher thread, mysql version %d",mysql_get_client_version());
 816         ModuleSQL* thismodule = (ModuleSQL*)arg;
 817         LoadDatabases(thismodule->Conf, thismodule->Srv);
 818
 819         /* Connect back to the Notifier */
 820
 821         if ((QueueFD = socket(AF_INET, SOCK_STREAM, 0)) == -1)
 822         {
 823                 /* crap, we're out of sockets... */
 824                 log(DEBUG,"QueueFD cant be created");
 825                 return NULL;
 826         }
 827
 828         log(DEBUG,"Initialize QueueFD to %d",QueueFD);
 829
 830         sockaddr_in addr;
 831         in_addr ia;
 832         inet_aton("127.0.0.1", &ia);
 833         addr.sin_family = AF_INET;
 834         addr.sin_addr = ia;
 835         addr.sin_port = htons(MessagePipe->GetPort());
 836
 837         if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
 838         {
 839                 /* wtf, we cant connect to it, but we just created it! */
 840                 log(DEBUG,"QueueFD cant connect!");
 841                 return NULL;
 842         }
 843
 844         log(DEBUG,"Connect QUEUE FD");
 845
 846         while (!giveup)
 847         {
 848                 SQLConnection* conn = NULL;
 849                 /* XXX: Lock here for safety */
 850                 pthread_mutex_lock(&queue_mutex);
 851                 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
 852                 {
 853                         if (i->second->queue.totalsize())
 854                         {
 855                                 conn = i->second;
 856                                 break;
 857                         }
 858                 }
 859                 pthread_mutex_unlock(&queue_mutex);
 860                 /* XXX: Unlock */
 861
 862                 /* Theres an item! */
 863                 if (conn)
 864                 {
 865                         log(DEBUG,"Process Leading query");
 866                         conn->DoLeadingQuery();
 867
 868                         /* XXX: Lock */
 869                         pthread_mutex_lock(&queue_mutex);
 870                         conn->queue.pop();
 871                         pthread_mutex_unlock(&queue_mutex);
 872                         /* XXX: Unlock */
 873                 }
 874
 875                 usleep(50);
 876         }
 877
 878         return NULL;
 879 }
 880
 881
 882 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 883
 884 class ModuleSQLFactory : public ModuleFactory
 885 {
 886  public:
 887         ModuleSQLFactory()
 888         {
 889         }
 890
 891         ~ModuleSQLFactory()
 892         {
 893         }
 894
 895         virtual Module * CreateModule(Server* Me)
 896         {
 897                 return new ModuleSQL(Me);
 898         }
 899
 900 };
 901
 902
 903 extern "C" void * init_module( void )
 904 {
 905         return new ModuleSQLFactory;
 906 }
 907